tricky h1-b situation w.r.t. I-94, extension and transfer

[Marbles_15]

Hi,

My H1 petition(I-797B) with current employer expired on March 31 2017, my i-94 at port of entry was issued till 2018 March. I had applied for extension in Feb 2017 under same employer and got rfe. Replied to it and USCIS resumed processing my rfe response. Meanwhile got new job with different employer, who wants to file for transfer with new petition next week i.e., on April 10th 2017. Can i join the new employer as soon as he files my new petition next week though my H-1 petition with current employer expired and extension under process. Will new transfer petition be treated as bridged petition because it was filed after my initial h1-b petition expired. Can i join new employer when extension request is being processed for current employer. my I-94 is still valid for a year so the time of filing new transfer petition will be dependant on previous h1-b extension result and treated as filed after h1-b got expired in which case it would be bridged petition or it will be independant of that since my I-94 is still valid. Please advise